This invention relates generally to doors for mine stoppings, and more particularly to a door system incorporating a novel latching mechanism for a so-called "man door" for use in connection with masonry and metal mine stoppings.
"Stoppings" are widely used in mines to stop off flow of air in mine passageways, or to inhibit access to the mines, a "stopping" generally being a masonry (e.g., concrete block) or metal wall installed at the entrance of a mine passage. It is often desired that such stoppings be provided with a door, which is referred to as a "man door", for occasional access to the blocked-off passage. A serious problem encountered, however, is providing a latching mechanism for the door which remains effective and operable to latch and unlatch the door in the event the walls of the mine shift or converge, which may result in deformation of the stopping and consequent jamming of the latch or inoperability of the latching mechanism.
Reference may be made to U.S. Pat. No. 4,082,331 for a stopping with a man door using a latching mechanism generally relevant to this invention.